package org.jeecgframework.core.util;

public class LocationUtils {
	private static double EARTH_RADIUS = 6378.137;

	private static double rad(double d) {
		return d * Math.PI / 180.0;
	}

	/**
	 * 
	 * 通过经纬度获取距离(单位：米)
	 * 
	 * 
	 * 
	 * @param lat1
	 * 
	 * @param lng1
	 * 
	 * @param lat2
	 * 
	 * @param lng2
	 * 
	 * @return 距离
	 * 
	 */

	public static double getDistance(double lat1, double lng1, double lat2, double lng2) {
		double radLat1 = rad(lat1);
		double radLat2 = rad(lat2);
		double a = radLat1 - radLat2;
		double b = rad(lng1) - rad(lng2);
		double s = 2 * Math.asin(Math.sqrt(
				Math.pow(Math.sin(a / 2), 2) + Math.cos(radLat1) * Math.cos(radLat2) * Math.pow(Math.sin(b / 2), 2)));
		s = s * EARTH_RADIUS;
		s = Math.round(s * 10000d) / 10000d;
		s = s * 1000;
		return s;

	}

	public static void main(String[] args) {
		double distance = getDistance(34.2675560000, 108.9534750000, 34.2464320000, 108.9534750000);
		System.out.println("距离" + distance / 1000 + "公里");

	}

}
